The basic user interface of AMG4PBLAS consists of eight methods. The six methods init, set, build, hierarchy_build, smoothers_build and apply encapsulate all the functionalities for the setup and the application of any multilevel and one-level preconditioner implemented in the package. The method free deallocates the preconditioner data structure, while descr prints a description of the preconditioner setup by the user. For backward compatibility, methods are also accessible as stand-alone subroutines.

For each method, the same user interface is overloaded with respect to the real/complex and single/double precision data; arguments with appropriate data types must be passed to the method, i.e.,

- the sparse matrix data structure, containing the matrix to be preconditioned, must be of type psb_xspmat_type with x = s for real single precision, x = d for real double precision, x = c for complex single precision, x = z for complex double precision;
- the preconditioner data structure must be of type amg_xprec_type, with x = s, d, c, z, according to the sparse matrix data structure;
- the arrays containing the vectors v and w involved in the preconditioner
application w = B
^{-1}v must be of type psb_xvect_type with x = s, d, c, z, in a manner completely analogous to the sparse matrix type; - real parameters defining the preconditioner must be declared according to the precision of the sparse matrix and preconditioner data structures (see Section 5.2).

A description of each method is given in the remainder of this section.

5.1 Method init

5.2 Method set

5.3 Method hierarchy_build

5.4 Method smoothers_build

5.5 Method build

5.6 Method apply

5.7 Method free

5.8 Method descr

5.9 Auxiliary Methods

5.9.1 Method: dump

5.9.2 Method: clone

5.9.3 Method: sizeof

5.9.4 Method: allocate_wrk

5.9.5 Method: free_wrk

5.2 Method set

5.3 Method hierarchy_build

5.4 Method smoothers_build

5.5 Method build

5.6 Method apply

5.7 Method free

5.8 Method descr

5.9 Auxiliary Methods

5.9.1 Method: dump

5.9.2 Method: clone

5.9.3 Method: sizeof

5.9.4 Method: allocate_wrk

5.9.5 Method: free_wrk